1. Field of the Invention
The invention relates to call answering or voice mail systems, and methods of operation thereof, and particularly but not exclusively to call answering systems traditionally having a centralised storage means for storing voice messages.
2. Description of the Related Art
In general, a required capability of telephony systems is to offer messaging services. Both public systems, such as central office systems and mobile cellular systems, and private systems offer messaging services. Messaging services are typically provided for incomplete calls, that is for calls where a connection to a called user is not completed. Messaging services generally allow a caller to leave a voice message for a user following an incomplete call. This is generally known as “call answering”, and typically is initiated when a call is made to a phone which is busy or which is not answered within a predetermined number of rings.
Call answering functionality is generally provided by providing a user of a system with a voice mailbox, which is hosted by a voicemail system within the telephony system. The user of such a system may also be known as a subscriber of the system. The voicemail system equipment typically contains the required logic to answer the telephone call, play a greeting message to the caller, and to record a voice message from the caller. The voicemail system typically further contains a persistent storage mechanism, a portion of which is provided for storage of voice messages for a particular user or subscriber.
Thus, each user or subscriber typically disadvantageously creates a cost which is associated with the storage resources necessary for providing a voicemail mailbox, as well as the management and administration tasks associated with the voicemail storage.
Voicemail systems provided in conjunction with private branch exchanges (PBXs) tend to be highly functional systems offering not only call answering functionality, but other messaging functionality. This other messaging functionality may include over-the-phone subscriber access to enable retrieval of messages stored in a subscriber mailbox, and inter-personal messaging capability, i.e. the capability of subscribers to compose and send voice messages directly to other voicemail subscribers within the system.
In public telephony network deployments, the inter-personal messaging capability is typically not provided, such as in residential land-line voice messaging systems and cellular telephone voice messaging systems.
However, in all systems where call answering functionality is provided, either in private or public telephony systems, there is a requirement for the service supplied to be managed and the message storage paid for.